Inner tube and rubber valve



May 26, 1964 s, MGCQNKIE 3,134,420

INNER TUBE AND RUBBER VALVE Original Filed Feb. 26, 1958 FIG] INVENTOR.

HOWARD S. McCON KlE A TTORNEYS.

United States Patent 3,134,423 INNER TUhE AND RUBBER VALVE Howard S.McConirie, 101 Etter Sh, Hot Springs, Ark. Original application Feb. 26,1958, Ser. No. 717,625, new Patent No. 3,038,517, dated June 12, 1962.Divided and this application Feb. 8, 1962, Ser. No. 171,986 6 Claims.(Cl. 152-429) This invention relates to tubeless type tires, moreparticularly to a tubeless tire provided with a floating or semifloatinginner tube for blowout protection, and is a division of copendingapplication, Serial No. 717,625, filed February 26, 1958, now Patent No.3,038,517, June 12, 1962.

While tubeless tires have gained general commercial acceptance, they aresubject to a number of disadvantages including vulnerability to blowoutor sudden collapse with consequent danger to the occupants of theautomobile; and difliculty in, and need for, special tools to installthe tires on the vehicle wheel rims so as to bulge the tire beads intosealing engagement with the rim to permit inflation.

It is a primary object of this invention to obviate these disadvantagesby provision of an inner tube entirely, or nearly entirely, floatedwithin the tire to provide safety against sudden puncture of the tire,and to enable installation of the tire to the rim without need forspecial tools.

It is a further object of the invention to provide a double aircompartment within a tubeless type tire, one compartment completelysurrounding the other, except at possible points of attachment.

Yet another object is to provide an inner tube which can be installedcompletely within a conventional tubeless tire on a conventional wheelrim of any type including drop center.

Still another object is to provide a safety member for tubeless tiresfor security in event of blowout without sacrificing the comfort of orother qualities of the ride and performance of the tire.

A still further object is to provide an inner tube for tubeless tireswhich is easy to mount and inflate and which enables the tubeless tireitself to be more easily mounted and inflated.

Yet another object is to provide an inner tube, for a conventionaltubeless type tire, of simple construction and relatively inexpensive tomanufacture.

The novel features that are considered characteristic of the inventionare set forth with particularity in the appended claims. The inventionitself, however, both as to its organization and its method ofoperation, together with additiond objects and advantages thereof, willbest be understood from the following description of specificembodiments when read in connection with the accompanying drawings,wherein like reference characters indicate like parts throughout theseveral figures and in which:

FIG. 1 is a transverse radial section of a tubeless tire mounted on adrop-center rim assembled with an inner tube according to the invention.

FIG. 2 is an enlarged fragmentary sectional view of the tube valvearrangement shown in FIG. 1, and

FIG. 3 is a View similar to FIG. 2, showing a modified valve structure.

Referring now to the drawings, the invention is shown in FIG. 1 asembodied in an inner tube 60.which is floated at least partially freelyentirely within a conventional tubeless tire 12 mounted on a drop-centerwheel rim 14. The details of construction of the tire are well known tothose skilled in the art and need not be described here. It issnflicient to say that the tire has the usual tread 16, sidewalls 18 andrim engaging beads 26.

The inner tube 61?, similar to tubes of conventional 3,134,420 PatentedMay 26, 1964 construction as used with tubed tires, is modified as shownin the drawing, and comprises a thin Walled endless rubber tube,doughnut shaped when inflated, and is inflatable through special valvesto be described later.

The tire 12 is inflated by means of an inflation valve 32 including astern body 34 which protrudes through a hole 36 in the wall of thedrop-center rim 14. The valve 32, preferably, is the usual type ofrubber bodied valve employed with tubeless type tires and the rim hole36 is air sealed by means of a snug fit of the rim portion surroundingthe hole 36 within an annular recess 38 surrounding the stem. The valvestem 34 and removable valve core with protruding nipple designated 44,may be of conventional construction generally in use with tubelesstires.

In FIG. 1 is illustrated an inner semifloating tube 60 which is providedwith a pair of flutter valves 62, 64. As best shown in FIG. 2, thesevalves are cooperatively disposed on opposite sides of a wall of thetube 60, in operative relation to an opening 66 in the tube wall, tooperate in opposite directions. The flutter valves are each soft rubbervalves of conventional construction which permit movement of air in onedirection only except under extreme surges of pressure. Valves 62 and 64being opposed, prevent air from entering or leaving the tube 60 once thetube is inflated. In lieu of the flutter valves 62, 64, conventionalflap or leaf valves 62', 64', as shown in FIG. 3, may be disposed onopposite sides of the tube wall 69' in covering relation to an opening66' therein.

To install the tire 12 and tube 10, the operator will first remove thestem 34, or if the stem is oversize he will remove the core 44 fromvalve stem 34. He will next insert one beaded edge 20 of tire 12 intothe drop-center channel of the rim. The deflated tube 60 is theninserted in the tire 12 with the valve 64 positioned in the rim opening36 or in the valve stem 34 from which the core has been removed, andheld as so positioned if desired by a hollow needle stem to be used forpassing inflating air to the tube. The other beaded edge 20 of the tire12 is next mounted or inserted into the drop-center channel of the rim.

To inflate tube 60, the hollow needle valve stem (not shown) which hasbeen carefully inserted through stem 34 and through valves 64 and 62 (orpast valves 62', 64') and through stem 34 if the stem is not removed,and held in alignment with the opening or stem, is used to fill tube 60with inflating air and the needle is then withdrawn. The operator maybefore Withdrawal of the needle, to insure against leakage or effusionof air from tube 60 after the tire is inflated, apply a small amount ofrubber cement through the hollow needle valve stem to the lips of theouter flutter valve 64, the inner flutter valve 62, or both, whichvalves are accessible through the rim opening or stem 34. Normally,however, the paired flutter valves will prevent such leakage. Whencementing is to be used, one flutter valve is suflicient if considerablecare is exercised.

Preferably, about half the operating pressure of the tire is used in thetube, or about 1015 lbs/square inch, for pleasure vehicles. Thispressure will extend tube 60 to fill the entire space within the tireand bulge the tire walls 18 and beads 26 outwardly so that both beadededges 20 press against the rim seats 46 in air sealing engagement, orsufliciently so that when higher pressure is placed in the tubeless typetire, as later described, the beads will move into the usual completeair sealing engagement with the rim.

Air is then fed through valve 32 into the tire 12 until an operatingpressure from 20-30 lbs/square inch is reached. This will compress tube60 and surround it with a cushioning rim of air in space 30. It isapparent speeds. reasonably avoided by applying balancing centrifugal'use asa fully free floating inner tube.

that the installation'process described is simple and easy to performand needs no special tools, avoiding the requirement for externalperipheral compressing devices normally used toin'stall tubeless tireswhich expand the beaded edges against the rim seats 46.

In use of the. tire with greater pressure therein than originally placedin the tube 60, the tire will carry the load and the tube, as a safetydevice, will float freely therein with some relative rotational movementat high Any-resulting vibration and unbalance may be weights to thetube, not shown. I

. When the tire 12 suffers a leak, crack, puncture or blowout, the airwill be released from space 30; tube 60 Will expand to fill the tire.The tube 60 will safely carry the weight of the vehicle for anindefinite period, but the soft appearance of the tire will indicateneed for repair.

To repair the tire after a puncture, which requires removal of the tirefrom the rim, valve core 44 is removed, and a hooklike instrument, notshown, may be inserted through stem 34 to seek and align the fluttervalve with the stern 34 for reinsertion of the needle valve to deflatethe tube. If the tube is fully free floating, however, it is probablethat the flutter valve is displaced from the stem 34 and in this event,it will be necessary to insert a sharp instrument to puncture the tube.When the air in tube'60 is released and the deflated tube and tireremoved from the rim, both the tire and the tube may be repaired.

The inner tube 60 may be secured to the inner surface of tire12at one ormore circumferentially spaced protrusions 50. If desired, thissecurernent maybe continuous in a broad line circumferentially of theouter periphery of the tube. Preferably, the securement is made atpoints spaced slightly to one side of the center of the tire as thiswill lessen the likelihood of puncturing the tube. The securement may beaccomplished by placing rubber cement on the inner wall of the tire atthe spots where attachment is desired. When the tube is inflated, itwill adhere to the cemeted spots.

As an alternative, the the and tube may be vulcanized together duringmanufacture. When the tire is inflated,

the tube 60 willbe compressed to provide the air space.

between the tube and tire everywhere except at the protrusions 50. Thesecurement of the tube to the tire at protrusions 50 greatly limitsrelative movement which might otherwise occur at high speeds ofrotation. 7

While the tubes herein referred to may be of wholly rubber construction,alternatively they may be so-called safety tubes of the well known typehaving a protectively reinforced dome portion to resist friction with orpinch-.

ing by the tire, or puncture by a sharp object. 7

The inner tubewith flutter valve is ideally suited for While the use ofhelium, carbon monom'de or other gas that is lighter than air should beconsidered for use in any floating inner tube, it should be ofparticular importance when used in this flutter valved floating tube.

Another advantage for the floating inner tube as described for use in atubeless type tire is the decrease in inertia in the initial stages ofabruptly changing the rotational rate of the .tire, tube and wheel rimassembly. In abrupt acceleration of a'motor vehicle, the floating tubewill not increase its rate of revolution as rapidly as the tire itself.It can be said to slip for awhile. It will, in fact never rotate as fastas the tire during acceleration nor while'maintaining a constant rate ofrevolution. It is moved in rotation only by the air stream within the arim. Since it takes a considerable amount of energy to rotate an innertube, the adoption of this floating tube will permit faster accelerationfor pneumatic tubeless type tire assemblies as described. 7

The reverse will be true when decelerating, especially when applyingbraking power to decrease the rate of revolution of this assembly. Thegeneral application of these savings will be considerable and may be ofparticular significance to race track vehicles where a great deal ofabrupt acceleration and deceleration is of vast im-.

portance. As stated above, bringing the tire and wheel rim to an abruptstop will not stop the tubes revolving immediately; In fact, the energyof this revolving tube can be utilized in again abruptly starting itsuch'start is undertaken before the tube ceases to rotate. On muddy racetracks and on the. highways during icy road conditions, this can be amatter of considerable importance.

What is claimed and desired to be secured by Letters Patent is:

1. 'An inner tube comprising a continuous doughnutshaped body at leastpartially formed of an elastic rubberlike material, a single valveopening in the Wall of said body, and a pair of flutter valvesoppositely disposed on the outside and inside of the body to preventingress and V cation of a hollow needle through said valve opening and 1past at least one of said flutter valves.

2. An inner tube according to claim '1 wherein the flexible tubularconduit associated with the outer domeshaped member extends outwardlyand the flexible tubular conduit associated with the inner dome-shapedmember extends inwardly of the tube body.

3. In combination, a tubeless tire mounted in air sealing engagementwith a wheel rim, an opening in' said rim and a valve stem in saidopening communicating with the space within the tire for admitting airto the tire, a continuous, hollow, annular inner tube within said tireand spaced from the walls of the tire and from said rim, a single valveopening only in a wall portion of said inner tube adjacent the rim, apair of opposed, aligned flutter valves mounted on opposite sides ofsaid valve opening and operative to prevent ingress of air to and egressof air from the inner tube except by application of a hollow inflatingneedle through said rim opening and valve opening.

4. The combination according to claim 3 wherein protrusions are providedat spaced points on the inner tube and secured to the inner surface ofthe tire.

5. The combination according to claim 3 wherein at least one of saidflutter valves is closed by cement.

6. The combination according to claim 3 wherein each of said fluttervalves comprises a flap of yieldable material secured at one side ofsaid valve opening and pressed against the opening to seal it by airpressure.

References. Cited in the file of this patent UNITED STATES PATENTS

1. AN INNER TUBE COMPRISING A CONTINUOUS DOUGHNUTSHAPED BODY AT LEASTPARTIALLY FORMED OF AN ELASTIC RUBBERLIKE MATERIAL, A SINGLE VALVEOPENING IN THE WALL OF SAID BODY, AND A PAIR OF FLUTTER VALVESOPPOSITELY DISPOSED ON THE OUTSIDE AND INSIDE OF THE BODY TO PREVENTINGRESS AND EGRESS OF AIR THROUGH SAID VALVE OPENING ONCE THE TUBE ISFILLED, EACH OF SAID FLUTTER VALVES BEING A DOME-SHAPED MEMBER HAVING ANOPENING SEATING ONE END OF A FLEXIBLE TUBULAR CONDUIT, THE OTHER END OFSAID CONDUIT BEING SPLIT TO PROVIDE FLAPS CLOSABLE BY PRESSURESURROUNDING THE CONDUIT, SAID BODY BEING ADAPTED TO BE INFLATED BYAPPLICATION OF A HOLLOW NEEDLE THROUGH SAID VALVE OPENING AND PAST ATLEAST ONE OF SAID FLUTTER VALVES.